A novel electrochemical sensor based on Fe3+-curcumin/multi-walled carbon nanotubes complex enabling electrochemical sensing of hydroxylamine

This work reported a novel electrocatalyst, Fe3+-curcumin/multi-walled carbon nanotubes (MWCNTs) complex, for efficient detection of hydroxylamine by modifying the glassy carbon electrode (Fe3+-curcumin/MWCNTs-modified electrode). The Fe3+-curcumin/MWCNTs complex was prepared via a green and facile one-pot synthesis method and the as-prepared complex was characterized using TEM, EDS, XRD, XPS, and EIS. Subsequently, the Fe3+-curcumin/MWCNTs complex modified electrode was adopted as an electrochemical sensor for hydroxylamine detection. The catalytic peak current for sensing the hydroxylamine using the Fe3+-curcumin/MWCNTs-modified electrode was 9.5 times higher the catalytic peak current using the curcumin/MWCNTs-modified electrodes. The overpotential was reduced by 550 mV compared to MWCNTs-modified electrodes. The interfacial electron transfer rate was 0.37 s−1 for the Fe3+-curcumin/MWCNTs-modified electrode. Furthermore, the Fe3+-curcumin/MWCNTs-modified electrode exhibited outstanding sensing performance within analyte concentration range from 0.05 to 1100 μM (a low detection limit of 0.02 μM, S/N = 3). Finally, the constructed sensor was successfully adopted for the hydroxylamine detection from the hydrolysis of the pralidoxime iodide injections, demonstrating the practical applications.